If you don't know how to fix the dynamic bones on this model you will need to put the Root_MiddleUpperButtTail1 back in Armature and put all the tail bones onto it and that should fix it that specific bone will be in the ghastly fox girl model here https://vrcmods.com/item/932-Ghastly-the-Fox-Girl-dynamics-eyetracking-blinking-emotes- i hope this helps and fixes your problem. :3